1. Field of the Invention
The present invention relates generally to cooling systems for heavy duty truck engines and, more specifically, to a radiator assembly for a cooling system for a heavy duty truck engine.
2. Description of the Related Art
Internal combustion engines generate heat which must be dissipated or otherwise transferred from the engine to a heat sink such as ambient air surrounding the engine and its components. In a motor vehicle, a cooling system is the heat sink for the engine. Motor vehicle cooling systems typically include flow passages for fluid coolant which passes through a cooling jacket portion of an engine block for the engine and the flow passages are coupled in fluid coolant communication with a fluid coolant reservoir through hoses or the like. Fluid coolant reservoirs are commonly referred to as radiators and transfer heat from fluid coolant in the cooling system to the ambient atmosphere through a plurality of heat transfer mechanisms in a core of the radiator. More specifically, such radiators typically include a radiator core having a pair of tanks fixedly secured to either end thereof. Such radiators usually employ a gasket at the juncture between the tanks and the radiator core to facilitate fluid communication from one tank to the radiator core and from the radiator core to another tank as heat is transferred from fluid coolant in the cooling system to the ambient atmosphere surrounding the radiator.
Certain motor vehicles require greater cooling requirements than others. For example, the engines employed in freight vehicles of all sizes and especially those used in heavy duty trucks have substantial cooling requirements. Such vehicles typically operate using compression ignition or diesel engines and are designed for relatively long operating lives. Unfortunately and despite the longevity of such engines, the cooling systems employed and specifically the radiators employed have not enjoyed comparable operating life spans. Specifically, it is not uncommon for the plastic tanks on such radiators to fail under the repeated cycling of fluid coolant at elevated temperatures and pressures. Such failures include hairline cracks in the stress points of the tanks and broken bleeder flanges and petcocks and oblong flanges due to excessive clamping of hoses to prevent coolant seepage. Further, such radiators often employ inferior fastening mechanisms at the tank/header juncture. These fastening mechanisms include a plurality of crimp tabs disposed along a perimeter of the header. However, these crimp tabs become stressed and weakened due to excessive retightening, thus allowing fluid coolant to leak over time and leading to tank/header separation. Such fluid coolant leaks ultimately result in loss of fluid coolant, which, if undetected, can also lead to engine overheating, cracked engine blocks and blown head gaskets. More importantly, such fluid coolant leaks can result in higher down time costs and loss of income for such vehicles.